Over recent years, the market for wireless communications has enjoyed tremendous growth. Wireless technology now reaches or is capable of reaching virtually every location on earth. This rapid growth in wireless communication technology and portable computing platforms has led to significant interest in the design and development of instantly deployable, wireless networks often referred to as “ad-hoc networks”. Indeed, significant effort has been directed toward optimizing network performance within such ad-hoc networks.
The application of ad-hoc networks spans several different sectors of society. In the civilian sector, an ad-hoc network may be used to interconnect working groups moving in an urban or rural area, in hospital settings, and on a campus engaged in collaborative operations, such as, distributed scientific experiments. In the law enforcement sector, an ad-hoc network may be employed in situations such as crowd control, border patrol, and search and rescue operations. In the military sector, modern communications in a battlefield or in a special operations context require a very sophisticated instant infrastructure with complex requirements and constraints pertaining to network security, capacity, latency, and robustness.
Nodes within an ad-hoc network typically communicate using a single, predetermined, radio frequency (RF) capability that defines a communication channel, modulation technique, bandwidth, security, and so forth. Such RF capabilities can include, for example, satellite communications (SATCOM); single channel ground-to-air radio system (SINCGARS); Enhanced Position Location and Reporting System (EPLRS); Wideband Network Waveform (WNW); very high frequency, frequency modulation (VHF FM); very high frequency, amplitude modulation (VHF AM); APCO 25; mobile user objective system (MUOS), and so forth.
However, in some operational scenarios, commercial and military nodes often need-to communicate, or could benefit by having the capability of communicating, with two or more radio networks external to the ad-hoc network. These external radio networks may communicate using disparate RF capabilities that circumscribe frequency bands (e.g., High Frequency, Very High Frequency, Ultra High Frequency, L-Band, and above), modulation techniques (e.g., Amplitude Modulation, Frequency Modulation, Phase Shift Keying, Quadrature Phase Shift Keying, Binary Phase Shift Keying, Code Division Multiple Access, Time Division Multiple Access, and so forth), lower probability of intercept/detection techniques (e.g., spread spectrum), anti-jamming techniques (e.g., frequency hoping), multi-input/multi-output communications waveforms, and so forth.
In an attempt to facilitate communication with two or more external radio networks having disparate RF capabilities, individuals may be compelled to carry multiple different radios. Alternatively, radios that can switch between similar waveforms, for example, dual-band and tri-band cellular radios may be employed. Other proposed solutions entail the use of software definable radios that allow the radios to switch between waveforms and retune RF sections under software control so that the operator can switch between the external radio networks. Each of these current solutions has operational problems associated with them. Size, weight, power, battery life, cost, and complexity of use are a few of the significant issues.
An ideal solution would be a multiple channel, multiple band, multiple waveform radio that can simultaneously receive and transmit on any network of interest with the power necessary to communicate at long ranges. Unfortunately, such an implementation is not viable in a lightweight form factor, having a battery that would last an acceptable duration, and that can simultaneously transmit and receive on multiple networks without causing interference between channels.